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991.
992.
本文调查了三组中国企业管理人员的态度。内容涉及他们对创业的兴趣以及他们对于创业成功机会的预期,并试图通过此类调查找到一些普遍性。这些将对企业家领域的政策制定者有所帮助。  相似文献   
993.
Neuroimaging research has brought major advances to child health and wellbeing. However, because of the vulnerabilities associated with neurological and developmental conditions, the parental need for hope, and the expectation of parents that new medical advances can benefit their child, pediatric neuroimaging research presents significant challenges to the general problem of consent in the context of research involving children. A particular challenge in this domain is created by the presence of therapeutic misconception on the part of parents and other key research stakeholders. This article revierws the concept of therapeutic misconception and its role in pediatric neuroimaging research. It argues that this misconception can compromise consent given by parents for the involvement of their children in research as healthy controls or as persons with neurological and developmental conditions. The article further contends that therapeutic misconception can undermine the research ethics review process for proposed and ongoing neuroimaging studies. Against this backdrop, the article concludes with recommendations for mitigating the effects of therapeutic misconception in pediatric neuroimaging research.  相似文献   
994.
Combinations of drugs are increasingly being used for a wide variety of diseases and conditions. A pre-clinical study may allow the investigation of the response at a large number of dose combinations. In determining the response to a drug combination, interest may lie in seeking evidence of 'synergism', in which the joint action is greater than the actions of the individual drugs, or of 'antagonism', in which it is less. Two well-known response surface models representing no interaction are Loewe additivity and Bliss independence, and Loewe or Bliss synergism or antagonism is defined relative to these. We illustrate an approach to fitting these models for the case in which the marginal single drug dose-response relationships are represented by four-parameter logistic curves with common upper and lower limits, and where the response variable is normally distributed with a common variance about the dose-response curve. When the dose-response curves are not parallel, the relative potency of the two drugs varies according to the magnitude of the desired effect and the models for Loewe additivity and synergism/antagonism cannot be explicitly expressed. We present an iterative approach to fitting these models without the assumption of parallel dose-response curves. A goodness-of-fit test based on residuals is also described. Implementation using the SAS NLIN procedure is illustrated using data from a pre-clinical study.  相似文献   
995.
For ethical reasons it is important to try to obtain as much useful information as possible from an animal experiment whilst minimizing the number of animals used. Crossover designs, where applicable, provide an ideal framework for achieving this. If two or more treatment factors are included in the crossover design then the reduction in total animal usage can be considerable. In this paper we consider such designs, defined as multi-factor crossover designs. The designs are applicable when there are several different treatment factors, each at t levels, to be applied to the experimental units. The motivation for investigating these designs was a study conducted at GlaxoSmithKline to determine the preference of male and female dogs for t=5 different types of bed and t=5 different bedding conditions. A construction method is given for forming universally optimal designs for t not too large. Also given is an example for the special case where the number of treatment levels t=6.  相似文献   
996.
We consider a Bayesian analysis method of paired survival data using a bivariate exponential model proposed by Moran (1967, Biometrika 54:385–394). Important features of Moran’s model include that the marginal distributions are exponential and the range of the correlation coefficient is between 0 and 1. These contrast with the popular exponential model with gamma frailty. Despite these nice properties, statistical analysis with Moran’s model has been hampered by lack of a closed form likelihood function. In this paper, we introduce a latent variable to circumvent the difficulty in the Bayesian computation. We also consider a model checking procedure using the predictive Bayesian P-value.  相似文献   
997.
Voracek M  Egle J  Schleicher S  Loibl LM  Sonneck G 《Omega》2007,55(4):279-296
Convergent lines of evidence from adoption, family, geographical, immigrant, molecular genetic, surname, and twin studies of suicide point to genetic contributions to risk factors for suicidal behavior. Related mental health literacy (knowledge and beliefs) of professionals and laypersons may, however, lag behind this research progress. The purpose of this study was to further validate the 22-item Beliefs in the Inheritance of Risk Factors for Suicide Scale (BIRFSS), a novel instrument for assessing individuals' beliefs in the genetics of suicide. Data from a general population sample of 159 Austrian adults showed adequate internal scale consistency. Due to deliberate content heterogeneity, the instrument has a subscale structure, but factor analysis of items extracted a dominant first factor. BIRFSS scores were positively related to overall and specific knowledge on suicide facts (convergent validity), whereas unrelated to the Big Five personality dimensions, locus of control, social desirability, and verbal intelligence (discriminant validity). Demographic correlates of BIRFSS scores included respondents' age and religiosity (both positive ones), but not respondents' sex, educational level, or political orientation.  相似文献   
998.
Barr P  Cacciatore J 《Omega》2007,56(4):331-348
The study was an empirical examination of the relation of personality proneness to "problematic social emotions"--envy (Dispositional Envy Scale), jealousy (Interpersonal Jealousy Scale), and shame and guilt (Personal Feelings Questionnaire-2)--to maternal grief (Perinatal Grief Scale-33) following miscarriage, stillbirth, neonatal death, or infant/child death. The 441 women who participated in the study were enrolled from the Website, e-mail contact lists, and parent support groups of an organization that offers information and support to bereaved parents. All four problematic emotions were positively correlated with maternal grief. Envy, jealousy, and guilt made significant unique contributions to the variance in maternal grief. Overall, time lapse since the loss and the four problematic emotion predispositions explained 43% of the variance in maternal grief following child bereavement.  相似文献   
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